The effect of exercise on anxiety- and depression-like behavior of aged rats.

We investigated the effects of exercise in multiple sessions on anxiety- and depression-like behavior during aging, and the role of serotonin and serotonin 1A receptors in this process. Both 24-month-old (aged) and 6-month-old (adult) female rats were divided into five groups; aged control, adult control, aged + serotonin re-uptake inhibitors (SSRIs), aged + exercise, and aged + SSRIs + exercise. After exercise, all groups were evaluated using the open field arena, elevated plus maze and forced swim tests. We assessed serum corticosterone levels; number of amygdala, hippocampus and prefrontal cortex cells; tissue serotonin and serotonin 1A (5-HT1A) levels. In the open field test, aged rats exhibited a significant increase in locomotor activity compared to the SSRIs and SSRIs + exercise groups. During the elevated plus maze test, aged rats were observed less frequently in the open arms of assembly compared to adults. The duration increased in the exercise group and remained unchanged in the SSRIs group. In the forced swim test, the aged rats were more immobile compared to adults; no change was observed in the immobility time between these groups. The tissue serotonin levels in amygdala and hippocampus were higher in SSRIs + exercise group compared to the aged, exercised and SSRIs groups. The number of cells in the hippocampus, prefrontal cortex and amygdala decreased in the aged group compared to adult rats; increased numbers of cell were observed in exercise, SSRIs and SSRIs + exercise groups compared to aged rats. Exercise in multiple sessions may increase the number of cells in the hippocampus, prefrontal cortex and amygdala, which may reduce senile anxiety and depression. Also, serotonin and serotonin 1A receptors may play role in depression-like behavior.

Dose dependent effects of oxytocin on cognitive defects and anxiety disorders in adult rats following acute infantile maternal deprivation stress.

Maternal deprivation at an early age is a powerful stressor that causes permanent alterations in cognitive and behavioral functions during the later stages of life. We investigated the effects of oxytocin on cognitive defects and anxiety disorders caused by acute infantile maternal deprivation in adult rats. We used 18-day-old Wistar albino rats of both sexes. The experimental groups included control (C), maternally deprived (MD), maternally deprived and treated with 0.02 µg/kg oxytocin (MD-0.02 µg/kg oxy), maternally deprived and treated with 2 µg/kg oxytocin (MD-2 µg/kg oxy). When the rats were 60 days old, the open field (OF) and elevated plus maze (EPM) behavioral tests, and the Morris water maze (MWM) test for spatial learning and memory were performed. In addition, the number of neurons in the hippocampus, prefrontal cortex (PFC) and amygdala were determined using quantitative histology. We also measured vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) levels in the PFC. In both sexes, the MD group failed the learning test and the MD-2 µg/kg oxy group failed in the memory test. The MD-0.02 µg/kg oxy group spent more time in the open arm of the EPM device and their locomotor activities were greater in the OF test. The VEGF and BDNF levels in the PFC were higher in the MD-0.02 µg/kg oxy groups than the other maternally deprived groups (oxytocin ±). The number of PFC neurons was low in all male maternally deprived (oxytocin ±) groups, while the number of amygdala neurons was low in both female and male maternally deprived (oxytocin ±) groups. Male rats were more affected by maternal deprivation; administration of oxytocin had dose-dependent biphasic effects on learning, memory and anxiety.

First trimester maternal serum PAPP-A levels and associated pregnancy complications in intrahepatic cholestasis of pregnancy.

PURPOSE: To investigate first trimester maternal serum pregnancy associated plasma protein A (PAPP-A) multiple of the median (MoM) in cases with intrahepatic cholestasis of pregnancy (ICP). Obstetric complications and relation with PAPP-A MoM were also evaluated. MATERIALS AND METHODS: This was a retrospective case-control study. After exclusions, for each ICP case, two controls with uncomplicated singleton pregnancies were randomly selected. PAPP-A MoM of ICP cases with and without obstetric complications, and the control group were compared with each other. RESULTS: Total incidence of ICP was 0.99 % (138/13988). The study included 113 singleton pregnant women. Rates of gestational diabetes mellitus (GDM), preeclampsia (PE), fetal growth restriction (FGR), preterm labor (PTL), and hypothyroidism in cases with ICP were 21.2%, 7.9%, 10.6%, 18.6%, and 5.3%, respectively. Median PAPP-A MoM were 0.93 in ICP group and 1.10 in control group (p > 0.05). PAPP-A MoM levels were not significantly different either between the ICP group with complicated pregnancies and the control group or between the ICP group without complicated pregnancies and the control group (p >0.05). CONCLUSION: ICP incidence was similar to other European countries. Rates of obstetric complications expecially GDM were higher than expected in general pregnant population. ICP is not considered as pregnancy complications that have low PAPP-A MoM levels.

Effects of voluntary and involuntary exercise on cognitive functions, and VEGF and BDNF levels in adolescent rats.

Regular treadmill running during adolescence improves learning and memory in rats. During adolescence, the baseline level of stress is thought to be greater than during other periods of life. We investigated the effects of voluntary and involuntary exercise on the prefrontal cortex and hippocampus, vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF) levels, and spatial learning, memory and anxiety in adolescent male and female rats. The voluntary exercise group was given free access to a running wheel for 6 weeks. The involuntary exercise group was forced to run on a treadmill for 30 min at 8 m/min 5 days/week for 6 weeks. Improved learning was demonstrated in both exercise groups compared to controls. Neuron density in the CA1 region of the hippocampus, dentate gyrus and prefrontal cortex were increased. Hippocampal VEGF and BDNF levels were increased in both exercise groups compared to controls. In females, anxiety and corticosterone levels were decreased; BDNF and VEGF levels were higher in the voluntary exercise group than in the involuntary exercise group. The adolescent hippocampus is affected favorably by regular exercise. Although no difference was found in anxiety levels as a result of involuntary exercise in males, females showed increased anxiety levels, and decreased VEGF and BDNF levels in the prefrontal cortex after involuntary exercise.

Effects of exercise and poor indoor air quality on learning, memory and blood IGF-1 in adolescent mice.

It is known that regular aerobic exercise enhances cognitive functions and increases blood insulin-like growth factor 1 (IGF-1) levels. People living in urban areas spend most of their time indoors and indoor air quality can affect health. We investigated the effects of aerobic exercise in poor and good air quality environments on hippocampus and prefrontal cortex (PFC) neurons, anxiety, and spatial learning and memory in adolescent mice. Poor air quality impaired spatial learning and memory; exercise did not affect learning or memory impairment. Exercise in a good air quality environment improved spatial learning and memory. Poor air quality increased apoptosis in the hippocampus and PFC. Both exercised and sedentary groups living in a poor air quality environment had lower serum IGF-1 levels than those living in a good air quality environment. Living in a poor air quality environment has negative effects on the hippocampus, PFC and blood IGF-1 levels in adolescent mice, but exercise did not alter the negative effects of poor air quality.

Progesterone treatment decreases traumatic brain injury induced anxiety and is correlated with increased serum IGF-1 levels; prefrontal cortex, amygdala, hippocampus neuron density; and reduced serum corticosterone levels in immature rats.

Traumatic brain injury (TBI) may cause neuropsychiatric problems, such as anxiety disorder, that have negative effects on cognitive functions and behavior. We investigated the effects of progesterone on traumatic brain injury induced anxiety in 7-day-old rat pups subjected to contusion injury. Progesterone treatment decreased TBI induced anxiety and serum corticosterone levels, and increased serum IGF-1 levels. Moreover, progesterone treatment increased amygdala, prefrontal cortex and hippocampal neuron density. We found a negative correlation between serum corticosterone levels and anxiety tests, and a positive correlation between serum IGF-1 levels and anxiety tests. In addition, progesterone treatment decreased serum corticosterone compared to the controls and sham. Our results indicate that single dose progesterone may be effective for treating anxiety caused by TBI.

Age-related changes in apoptosis in rat hippocampus induced by oxidative stress.

Also known as programmed cell death, apoptosis is a sequence of events that leads to elimination of cells without releasing harmful substances into the surrounding area. Apoptosis may be induced by intracellular or extracellular signals. Certain apoptotic signals activate mitochondrial pro-apoptotic events and increase reactive oxygen species (ROS). Increased ROS production may lead to oxidative stress. The goal of our study was to characterize age-related changes in apoptosis induced by oxidative stress in the hippocampus. Rats 2, 7, 21 and 38 days old, and adult rats were used for our study. Hippocampal CA1, CA2, CA3 and dentate gyrus apoptosis, and hippocampal superoxide dismutase (SOD), glutathione peroxidase (GPx) enzyme activities and thiobarbituric acid reactive substances (TBARS) levels were measured. We found that numbers of hippocampal neurons were low in rats 2, 7 and 21 days old (CA1, p < 0.001; CA3, p < 0.05; gyrus dentatus, p < 0.001). The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positive cell count was highest in the CA1 and dentate gyrus of 21-day-old rats. Among 21-day-old rats, the hippocampal TBARS levels and SOD enzyme activity were high, whereas GPx activity was low. These results demonstrate that the hippocampal CA1 and dentate gyrus of 21-day-old rats are more prone to damage by oxidative stress.

Effect of melatonin on testicular damage in streptozotocin-induced diabetes rats.

BACKGROUND: It is well known that diabetes mellitus is associated with impairment of testicular function. In the present study, we aimed to demonstrate the effect of melatonin on testicular damage in male rats with streptozotocin (STZ)-induced diabetes. METHODS: Male Wistar rats were divided into 4 groups: (1) control group, (2) melatonin-treated nondiabetic group, (3) diabetic group and (4) melatonin-treated diabetic group. Diabetes was induced by STZ injection. Melatonin was administered intraperitoneally at the dose of 10 mg/kg for 5 days. Testicular damage was examined by using hematoxylin and eosin staining and periodic acid-Schiff staining, and apoptosis was determined by terminal-deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL). Potential disorders associated with seminiferous tubular sperm formation were evaluated using the Johnsen score. RESULTS: Diabetic rats showed a reduction in seminiferous tubule diameter, increased thickening of the basement membrane in seminiferous tubules and degenerated germ cells. TUNEL-positive cells were significantly more numerous in diabetic rats than in control rats. Melatonin significantly attenuated the diabetes-induced morphological changes and germ cell apoptosis in the diabetic rat testis. The number of polymorphonuclear leukocytes was significantly decreased in group 4 when compared to group 3. CONCLUSIONS: These results suggest that intraperitoneal administration of melatonin for 5 days is a potentially beneficial agent to reduce testicular damage in adult diabetic rats, probably by decreasing oxidative stress.

Intestinal prostaglandin E2 expression in rats with obstructive jaundice.

AIM: How obstructive jaundice causes the intestinal barrier to be injured is still controversially discussed. In this study, we hypothesize that intestinal prostaglandin E (2), a cytoprotective factor, may be affected by the bile duct obstruction. MATERIALS AND METHODS: Four groups of Wistar-Albino rats were used: in Groups 1 and 3, the rats underwent a sham operation. In Groups 2 and 4, the common bile duct was doubly ligated. Relaparotomy was performed after one week in Groups 1 and 2, and after two weeks in Groups 3 and 4, and specimens of the jejunum, ileum and liver were obtained for intestinal PGE (2) analysis and histopathological evaluation. RESULTS: Jejunal and ileal PGE (2) levels had significantly decreased in two-week bile duct-ligated rats compared to one-week ligated rats and the sham group (p < 0.01). Tissue injury scores (Chiu score) of the ileum were significantly higher in the two-week and one-week ligated rats than in the controls (p < 0.01 and p < 0.05, respectively). The jejunal injury score was significantly higher in the two-week ligated rats compared to controls (p < 0.05). The ileal and jejunal injury scores were higher in the two-week ligated rats than in the one-week ligated rats (p < 0.01 and p < 0.05, respectively). Precirrhotic fibrosis was detected in all two-week ligated rats, but in only 7 of 10 one-week ligated rats. CONCLUSIONS: Obstructive jaundice associated with intestinal tissue injury and precirrhotic changes leads to reduced intestinal PGE (2)-levels, suggesting an adverse effect on the intestinal cytoprotective process.

Short-term melatonin treatment improved diabetic nephropathy but did not affect hemorheological changes in diabetic rats.

Increased oxidative stress and hemorheological disturbances may play very important roles in the development of microangiopathies in diabetes mellitus. This study was designed to determine the healing effect of melatonin on hemorheological parameters and diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. Wistar male rats were divided into four groups as control, untreated-diabetic, melatonin-treated control and melatonin-treated diabetic rats. Diabetes was induced by injecting streptozotocin (45 mg/kg, i.p.). Fourteen weeks after inducement of diabetes, melatonin (10 mg/kg) was administered intraperitoneally for 5 days to the rats. Erythrocyte deformability and aggregation were measured by laser differaction analysis (LORCA). Diabetic nephropathy was assessed by histopathologic evaluation and TUNEL stain in the diabetic kidney. Decreased erythrocyte deformability and increased erythrocyte aggregation indices were determined in the diabetic group. Melatonin treatment did not improve these hemorheological abnormalities. However, renal injuries were diminished in the melatonin-treated diabetic group compared to the untreated diabetic group. Also, melatonin had an antiapoptotic effect on the diabetic kidney. It was concluded that i.p. administration of melatonin for 5 days improved renal injury in diabetic rats, probably by decreasing oxidative stress, but did not affect hemorheological changes.

Plasma levels of nitrites, PGF1alpha, and nitrotyrosine in LPS-treated rats: functional and histochemical implications in aorta.

We investigated the effects of lipopolysaccharide (LPS) administration on plasma nitrite, nitrotyrosine and 6-keto prostaglandin F1alpha, (PGF1alpha) levels and the related resultant changes in function and histochemistry of aorta in rats. Plasma nitrite and PGF1alpha nitrotyrosine levels were analysed after 5 mg/kg intravenous LPS was administered to rats compared with those in non-treated rats. The distribution of nitrotyrosine in the aorta was studied immunohistochemically. The contractile responses of aortic rings to phenylephrine (PE) from both the LPS-treated and control rats were studied in the organ baths. There were increases in plasma nitrite, PGF1alpha, and nitrotyrosine concentrations of LPS-treated rats compared to non-treated rats. Immunoreactivity of nitrotyrosine residues were detected in the endothelial and smooth muscle cells in LPS-treated but not in control rat aorta. The contractile responses to PE of the LPS-treated rat aortic rings were significantly reduced as compared with those of control rat's. Incubation of the aortic rings from LPS-treated rats with cyclooxygenase inhibitor indomethacine or with a combination of indomethacine and nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) increased the contractile responses to the levels observed in control rats suggesting that both prostanoids and particularly nitric oxide (NO) are involved in the reduced contractile responses in LPS-treated rats. These results supported the view that LPS might cause an increment in both NO and PGI2 levels. This increase in the NO and PGI2 levels may be responsible from the reduction in responses of aorta to contractile agents in LPS-treated rats. Increased peroxynitrite formation in LPS-treated rats may lead to nitration of the tyrosil residues of the proteins in the aorta.

Plasma levels of nitrites, PGF1 alpha and nitrotyrosine in LPS-treated rats: functional and histochemical implications in aorta

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We investigated the effects of lipopolysaccharide (LPS) administration on plasmanitrite, nitrotyrosine and 6-keto prostaglandin F1 alpha (PGF1 alpha) levels and the relatedresultant changes in function and histochemistry of aorta in rats. Plasma nitrite and PGF1 alpha, nitrotyrosine levels were analysed after 5 mg/kg intravenous LPS was administered to rats compared with those in non-treated rats. The distribution of nitrotyrosinein the aorta was studied immunohistochemically. The contractile responses of aorticrings to phenylephrine (PE) from both the LPS-treated and control rats were studiedin the organ baths. There were increases in plasma nitrite, PGF1á, and nitrotyrosineconcentrations of LPS-treated rats compared to non-treated rats. Immunoreactivityof nitrotyrosine residues were detected in the endothelial and smooth muscle cellsin LPS-treated but not in control rat aorta. The contractile responses to PE of the LPStreatedrat aortic rings were significantly reduced as compared with those of controlrat’s. Incubation of the aortic rings from LPS-treated rats with cyclooxygenaseinhibitor indomethacine or with a combination of indomethacine and nitric oxide synthaseinhibitor Nù-nitro-L-arginine methyl ester (L-NAME) increased the contractileresponses to the levels observed in control rats suggesting that both prostanoids andparticularly nitric oxide (NO) are involved in the reduced contractile responses inLPS-treated rats. These results supported the view that LPS might cause an incrementin both NO and PGI2 levels. This increase in the NO and PGI2 levels may be responsiblefrom the reduction in responses of aorta to contractile agents in LPS-treated rats.Increased peroxynitrite formation in LPS-treated rats may lead to nitration of thetyrosil residues of the proteins in the aorta

Deprenyl and the relationship between its effects on spatial memory, oxidant stress and hippocampal neurons in aged male rats.

Oxidative stress may play a major role in the aging process and associated cognitive decline. Therefore, antioxidant treatment may alleviate age-related impairment in spatial memory. Cognitive impairment could also involve the age-related morphological alterations of the hippocampal formation. The aim of this study was to examine the relationship between the effects of deprenyl, an irreversible monoamine-oxidase B inhibitor, on spatial memory by oxidant stress and on the total number of neurons in the hippocampus CA1 region of aged male rats. In this study, 24-month-old male rats were used. Rats were divided into control and experimental groups which received an injection of deprenyl for 21 days. Learning experiments were performed for six days in the Morris water maze. Spatial learning was significantly better in deprenyl-treated rats compared to saline-treated rats. Deprenyl treatment elicited a significant decrease of lipid peroxidation in the prefrontal cortex, striatum and hippocampus regions and a significant increase of glutathione peroxidase activity in the prefrontal cortex and hippocampus. It was observed that deprenyl had no effect on superoxide dismutase activity. The total number of neurons in the hippocampus CA1 region was significantly higher in the deprenyl group than in the control group. In conclusion, we demonstrated that deprenyl increases spatial memory performance in aged male rats and this increase may be related to suppression of lipid peroxidation and alleviation of the age-related decrease of the number of neurons in the hippocampus. The results of such studies may be useful in pharmacological alleviation of the aging process.

Effect of melatonin on brain oxidative damage induced by traumatic brain injury in immature rats.

Progressive compromise of antioxidant defenses and free radical-mediated lipid peroxidation, which is one of the major mechanisms of secondary traumatic brain injury (TBI), has also been reported in pediatric head trauma. In the present study, we aimed to demonstrate the effect of melatonin, which is a potent free radical scavenger, on brain oxidative damage in 7-day-old rat pups subjected to contusion injury. Whereas TBI significantly increased thiobarbituric acid reactive substances (TBARS) levels, there was no compensatory increase in the antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) 24 hours after TBI in 7-day-old rats. Melatonin administered as a single dose of 5 mg/kg prevented the increase in TBARS levels in both non-traumatized and traumatized brain hemispheres. In conclusion, melatonin protects against oxidative damage induced by TBI in the immature brain.

Effects of acute footshock stress on antioxidant enzyme activities in the adolescent rat brain.

In a previous study we demonstrated that acute footshock stress increased glutathione peroxidase activity in the prefrontal cortex and striatum of adult male rats. Adolescents may respond differently to stress as life stressors may be greater than at other ages. The present study examined the effects of the acute footshock stress on superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities and thiobarbituric acid reactive substances (TBARS) levels in adolescent male and female rat brains. We demonstrated that acute footshock stress increased SOD activity in the prefrontal cortex, and increased GPx activity in the hippocampus in female rats. In males, acute footshock stress increased GPx activity in the prefrontal cortex and hippocampus. Footshock stress did not change TBARS levels. These results indicate a strong role of gender in the response of adolescent subjects to various aspects of stress.

Effects of melatonin on oxidative stress and spatial memory impairment induced by acute ethanol treatment in rats.

Melatonin has recently been suggested as an antioxidant that may protect neurons from oxidative stress. Acute ethanol administration produces both lipid peroxidation as an indicator of oxidative stress in the brain and impairs water-maze performance in spatial learning and memory tasks. The present study investigated the effect of melatonin against ethanol-induced oxidative stress and spatial memory impairment. The Morris water maze was used to evaluate the cognitive functions of rats. Thiobarbituric acid reactive substances (TBARS), which are the indicators of lipid peroxidation, and the activities of antioxidative enzymes (glutathione peroxidase and superoxide dismutase) were measured in the rat hippocampus and prefrontal cortex which form interconnected neural circuits for spatial memory. Acute administration of ethanol significantly increased TBARS levels in the hippocampus. Combined melatonin-ethanol treatment caused a significant increase in glutathione peroxidase activities and a significant decrease of TBARS in the rat hippocampus. In the prefrontal cortex, there was only a significant decrease of TBARS levels in the combined melatonin-ethanol receiving group as compared to the ethanol-treated group. Melatonin did not affect the impairment of spatial memory due to acute ethanol exposure, but melatonin alone had a positive effect on water maze performances. Our study demonstrated that melatonin decreased ethanol-induced lipid peroxidation and increased glutathione peroxidase activity in the rat hippocampus.

Pentoxifylline contributes to the hepatic cytoprotective process in rats undergoing hepatic ischemia and reperfusion injury.

AIM: Considerable efforts have been made to find and/or eliminate the underyling causes of hepatic ischemia-reperfusion injury, but many points are still unclear. Pentoxifylline-related cytoprotection is one of these unclear points. Our study tests the effects of pentoxifylline on the hepatic cytoprotective process in an experimental model. MATERIALS AND METHODS: The animals were divided into two groups: (1) placebo-pretreated rats and (2) pentoxifylline-pretreated rats. After pretreatment, all rats underwent the hepatic ischemia-reperfusion procedure which was performed by clamping the hepatoduodenal ligament. To evaluate the liver injury, serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), and liver tissue levels of prostaglandin E(2) (PGE(2)) were measured before ischemia, immediately after ischemia and immediately after reperfusion. RESULTS: Before ischemia and immediately after ischemia, there were no significant differences between ALT and AST levels of groups 1 and 2 (p >0.05). However, at the end of reperfusion, ALT and AST levels of group 2 were significantly decreased when compared with group 1 (p < 0.05 and p < 0.01, respectively). Additionally, tissue levels of PGE(2) that were obtained before ischemia, immediately after ischemia and immediately after reperfusion in group 2 were significantly higher than those of group 1 (p < 0.001). CONCLUSION: Pentoxifylline reduces reperfusion injury of the liver through significantly decreased transaminase levels, and contributes to hepatic cytoprotection by increasing tissue levels of PGE(2) significantly. These effects reflect the role of tissue PGE(2) in pentoxifylline-related hepatoprotection against ischemia-reperfusion injury of the liver.

Antioxidant enzyme levels in intestinal and renal tissues after a 60-minute exercise in untrained mice.

The present study was designed to determine the effects of exercise on the antioxidant enzymatic system and lipid peroxidation in small intestine and kidney, during the post-exercise period in untrained mice. Two days after the last adaptation running exercise, animals were ran on the treadmill for 60 min at 18 m/min. 5 degrees slope. After the acute exercise the animals were killed by cervical dislocation, immediately (0 h), 3 hours (3 h) and 24 hours (24 h) after the exercise. Control animals were killed without running exercise. Their proximal small intestinal and renal tissues were quickly removed. Changes in the concentration of thiobarbituric acid reactive substance (TBARS), as an index of lipid peroxidation, in intestine and kidney were studied in mice after the running exercise and in unexercised control group. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were determined in these tissues. Tissue SOD, GPx activities and TBARS level were not increase by the exercise in kidney. Intestinal SOD activity decreased after exercise (0 h and 3 h respectively, p<0.05, p<0.01) and retumed to control levels. Intestinal GPx activity increased after exercise (0 h, p<0.05) and returned to control levels. There was no significant difference among groups in intestinal tissue TBARS levels. These findings could suggest that submaximal exercise may not cause oxidative stress in proximal small intestinal tissue and kidney.

Methamphetamine causes depletion of glutathione and an increase in oxidized glutathione in the rat striatum and prefrontal cortex.

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. The hypothesis that methamphetamine-induced neurotoxicity is mediated by reactive oxygen species was evaluated. It was found that acute administration of methamphetamine (5 and 15 mg kg(-1)) resulted in production of oxidative stress as demonstrated by decreased glutathione and increased oxidized glutathione levels in the rat striatum and prefrontal cortex. These changes in glutathione and oxidized glutathione levels were dose-dependent in striatum but not in prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.

The effects of single dose of methamphetamine on lipid peroxidation levels in the rat striatum and prefrontal cortex.

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. In the present study, we demonstrated that a single dose (15 mg/kg) of methamphetamine results in production of oxidative stress as demonstrated by increased thiobarbituric acid reactive substances levels in the rat striatum and prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.